In the U.S., the typical egg is produced according to the Food and Drug Administration's (FDA's) guidelines for limiting Salmonella Enteritidis (SE) contamination. However, these parameters are not always sufficient to eliminate the possibility of contamination. Over 6.95 billion table eggs were produced in August 2013 in the United States. Given the large number of eggs consumed, it is likely under the current standards that eggs that are infected with SE will reach the consumer. Illness caused by the consumption of SE-contaminated eggs is a serious public health problem. The effects caused by SE infection may include mild to severe gastrointestinal illness, short term or chronic arthritis, and even death in some cases.
The current FDA procedures comprise requirements relating to pullets, biosecurity, pest and rodent control, cleaning and disinfection, storage, environmental testing and egg testing. Pullets must be raised under monitored conditions, with their environment tested for SE when the pullets are 14-16 weeks old, if this test is negative, a second test is conducted at 40-45 weeks of age and additional environmental tests are conducted 4-6 weeks after the end of each molt. If any of the environmental tests are positive, environmental cleaning and disinfection must be performed, and egg testing for SE must be conducted within two weeks of the start of laying. However, egg testing is not routinely conducted, but is required only if an environmental test is positive. This egg testing is conducted according to a specified schedule and eggs that were produced by a flock that had tested positive can be allowed to enter the market if a sufficient number of egg tests come back negative of SE contamination. Egg testing is conducted according to Chapter 5 of FDA's Bacteriological Analytical Manual, December 2007 edition, or a method that is equivalent in accuracy, precision, and sensitivity in detecting SE contamination.
The FDA provides suggestions and requirements for biosecurity measures that should be taken to prevent the introduction or transfer of SE into or among poultry houses. The minimum requirements include addressing cross-contamination from equipment and people moving among poultry houses. Additionally, the number of visitors to the farms should be limited and actions should be taken to prevent stray animals from accessing poultry houses.
Pest control is conducted by monitoring for rodents and flies, and taking appropriate action to achieve a satisfactory level of control. Additionally, debris and vegetation should be removed from within and outside of poultry houses. Cleaning and disinfection of a poultry house is only required if the environmental or egg testing revealed a positive test at any point in the life of the flock. Storage and transportation must be performed at temperatures at or below 45 degrees F. beginning 36 hours after time of lay.
These required processes are sufficient to provide an egg product that has a limited possibility of contamination. However, this process may allow a significant number of SE contaminated eggs to reach the end consumer.
In addition to concerns about SE contamination, there are other components of eggs that make them less desirable to consumers. These less desirable components include saturated fat, which is considered to have negative effects on cardiovascular health, which negatively impacts the consumption of eggs. The reduced consumption of eggs prevents people from obtaining many of the beneficial contents present in eggs, such as protein and numerous other nutrients. However, an egg's beneficial nutrients can be increased through specific supplements added to the feed consumed by the chickens. By increasing the amount of beneficial nutrients in an egg, the negative perception concerning egg contents may be overcome and greater benefits from consuming eggs may be realized.
The beneficial nutrients that can be increased in eggs include vitamins D and E, as well as Omega-3 fatty acids. Omega-3s are generally recognized for their ability to reduce triglycerides in the blood and lower blood pressure. Additionally, the consumption of omega-3s may be able to counteract some of the negative cardiovascular effects of saturated fats. However, most individuals in the United States do not consume a sufficient amount of Omega-3 fatty acids. Additional consumption of Omega-3 rich food sources, such as eggs, could possibly result in improved health of individuals. What is needed is a VESE that comprises vitamins and nutrients that have been shown to have beneficial health effects, such as vitamins E and D, and Omega-3 fatty acids, as well a reduced amount of saturated fat.
Certain characteristics regarding the physical properties of an egg also impact the consumers' perception of egg quality. The USDA grades the quality of an egg according to interior and exterior qualities, after which they are sorted by weight. Eggs can be graded AA, A or B quality, with AA being the highest quality and B the lowest.
Interior egg quality is graded by candling and breakout evaluation expressed by Haugh units. The interior quality is dependent on the properties exhibited by the albumen, yolk and air cell. The albumen is judged on the basis of clarity and thickness, with higher Haugh units assigned to eggs with a thicker albumen. Yolk quality is dependent upon the distinctness of its outline, size, shape, and absence of defects. Higher grade eggs have shallower air cells.
The exterior of the egg is examined for cleanliness, soundness, texture and shape. Shells cannot be broken, cracked or appear unsound. The ideal egg shape is oval, with one end slightly larger than the other end. Eggs with abnormal shells, including misshapen, poor textured, ridged, thin, or rough shells are classified as grade B.
Due to the USDA grading system and the consumer perception of less than desirable physical properties, it is important that any egg produced have desirable properties. Studies have shown that many of these physical properties, such as shell strength, yolk color and albumen height can be controlled through supplements provided in the diet of the laying hen and management practices applied to the flocks.
In order to ensure that an egg reaching the final consumer has been made according to the use of a particular process and all criteria set forth in the process have been met, each component of the process must be documented. Additionally, each egg must be traceable along every step of the process. Finally, marking on the egg must provide some notification to the consumer that it was produced under a strict set of conditions.
What is needed is a method of egg production and verification, which comprises processes that can significantly reduce the possibility that a egg contaminated with SE will reach consumers, increase the nutritional content and physical properties of the egg, reduce less desirable nutritional attributes of the egg, and identifies the egg as having these characteristics.